Dividing head for lathes



2 Sheets-Sheet ll INVENTOR LEO Hausa/Mmm nM/Z2, *gum* ATTORNEYS.

| HOLTSCHNEIDER DIVIDING HEAD FOR LATHES Filed Dec. 27, 1955 June 2, 1936.

mm mm l.. HOLTSCHNEIDER 2,042,847

DIVIDING HEAD FOR LATHES June 2, 1936.

Filed Dec. 27, 1953 2 Sheets-Sheet 2 ml iliii' nu HEEL ATTORNEYS.

Patented June-2, 1936 UNITED STATES PATENT OFFICE 10 Claims.

This invention relates to improvements in dividing heads for lathes and has for an object the provision of mechanism by means of which accurate angular rotation or adjustment of the lathe spindle may be eiected.

A further object of the invention is the provision of -an accurate worm gear on the lathe spindle preferably adjacent to the gear at the large end of the cone pulley.

Still another object of the invention is the provision of a swingable arm carrying a worm, a visual indicator for rotating the worm, and a suitable locking device for holding the worm into the proper engagement with the worm gear, whereby the locking device may be disengaged and the arm may be swung back out of the zone of the spindle, making the entire headstock of the lathe accessible from all points.

Heretofore some devices of this character have been provided with worms engaging the back gears, but the accuracy of such devices is limited because the back gears are spur gears and are not intended to cooperate with a worm. Other existing devices of thischaracter are attached through the medium of a face plate or a chuck but they have disadvantages in the loss of the time required to set them up, and the nature of the structures is less conducive to accuracy than the present invention which is built in and forms an integral part of the lathe itself.

Other objects and advantages of this invention will become obvious'to those skilled in the art upon a perusal of this specification and the appended claims.

Referring to the drawings:

Fig. 1 is an elevation partly in section of a preferred embodiment of the invention positioned on the head stock of a lathe;

Fig. 2 is an elevation partly in section of the device as viewed in a plane at right angles to the plane of elevation shown in Fig. 1;

Fig. 3 is a view of the device partly in section along the line 3-3 of Fig. 1;

Fig. 4V is a cross sectional view of the pivoted support as viewed along the line 4-4 of Fig. 1;

Fig. 5 is` an elevation partly in section of a modiaction of the hand wheel and Vernier shown in Fig. 1;

Fig. 6 is a sectional View taken along the line 6 6 of Fig. 5;

Fig. 7 is a view of the hand wheel showing a double vernier arrangement; and

Fig. 8 is an elevation of the locking plate showing its relation to the eccentric plunger.

Referring to Figs. 1 and 2, the head stock I 0 (Cl. S30- 56) of the lathe has its spindle II provided with a large gear I2. This gear is suitably keyed or otherwise fixed to the spindle yI I.

A worm gear I3 is provided between the gear I2 and the end bearing I4 and may be secured to the gear I2 by means of bolts I5, or any other suitable means. A clearance slot (not shown) is formed in the web of the Worm gear I3 to enable the cone I6 to be released when it is necessary to reduce the speed of the spindle by means of the big gear, when the lathe is in ordinary use. This releasing means has no bearing on the present invention and is not herein shown in detail. The projecting arm I1 of the head stock IU has secured thereto a bracket I8 by means of cap screws I9 and 20. This bracket has integral therewith a round boss 2l, one end of which is tapered. This tapered end is designated by the numeral 22 and a hole through the center of the boss is provided for the bolt 23. 'I'he bolt 23 is provided with a head 24 having a tapered shoulder 25. The end of the bolt opposite the head 24 is threaded to accommodate the nut 26 and this nut may be one of the locking variety, or the bolt 23 may be lengthened (not shown) and provided with two nuts 26, so that any desired adjustment of the bolt may be secured and this adjustment may be retained by means of the lock nut. The hole in the boss 2| may have a portion of its length threaded to t the threads on the bolt 23, in which case the desired adjustment may be obtained with the bolt 23 and this adjustment may then be retained by means of the nut 26 which would then serve as a locknut.

The main body 21 of the device houses the worm and Worm shaft, as will presently be described. The rear extension 28 of the body member 21 is made in the form of a boss, and a hole 29 in said boss is larger than and clears the bolt 23. Beveled depressions 30 and 3| are formed in either face of the boss 28 `and the beveled depression 30 is engaged by the face of the tapered shoulder 25, and the beveled depression 3l is engaged by the tapered end 22 of the boss 2l. The nut 26 is adjusted so that the angular surfaces of 30 and 3I bear freely and without lost motion against the surfaces of 25 and 22.

The main body 21 is provided with a bearing 32 for one end of the shaft 33. Near the other end of the shaft 33 a sleeve 34 is positioned thereon and forms therewith a bearing. The sleeve 34 has a threaded portion 35 at one end thereof, and a step 36 at the other end thereof is provided with a plurality of spanner holes 31. 'Ihe main body 21 is bored out and thread- Y with graduations in degrees.

ed to match the threads 35 on the sleeve 34, and a plain reamed hole members up with the midportion of the sleeve 34. The main body 21 is provided with a slot 38 and a locking bolt 39 is provided across the slot 38 and at right angles thereto for clamping the body against a portion of the sleeve 34 when a desired adjustment of the sleeve 34 is obtained. The shaft 33 is provided with a worm 48 which, when the device is positioned as shown in Fig. 1, engages the teeth of the worm gear I3. The shaft 33 is also provided with shoulders 4| and 42, and the shoulder 4I members up with the end 35 of the sleeve 34.

A hardened thrust member 43 is positioned at the bottom end of the hole forming the bearing 32, and a thrust Washer 44 is positioned between the end of the shaft 33 and the thrust member 43.

With the clamping bolt 39 loosened, the sleeve 34 by means of a Spanner wrench engaging the Spanner holes 31 may be rotated in either direction and substantially all end play in the shaft 33 may betaken up by screwing the sleeve 34 toward the thrust member 43. A Yfelt washer or any other suitable oil retainer 45 may be provided between the shoulder 42 and the inner face 43 of the interior of the body 21 adjacent to the bearing 32.

A disc or wheel 41 is provided with a hub 48 having a hole formed therein to fit the stepped endv 49 of the shaft 33 and is secured there by means of a taper pin 5B, or any other suitable means. The circumferential face of this wheel is provided with graduations designated by the numeral 5|. A suitable felt washer or oil ring 52 is provided between the inner face of the hub 48 and the adjacent end of the sleeve 34. A stationary disc or ring 53, which might be termed a Vernier ring, preferably of the same diameter as the wheel 41 is hollowed out to form a working lit upon the body member 21 along the surface indicated by the numeral 54. The circumferential face of this ring is also provided with graduations designated by the numeral 55, which cooperate with the graduations 5| above referred to. The ring 53 has a `clearance hole for clearing the felt ring 52 and is supported on the body r21 by a dowel pin 56, which may engage any one of a plurality of dowel holes in the Vernier ring 53. Another arrangement con-- templates formation of a plurality of utes on the Vernier ring engaging like flutes formed on the body 21 whereby the Vernier ring 53 may be adjusted to the best light position in the place where the lathe is set up.

rA plurality of compression springs 51 pressing against the ring 53 are provided for keeping Ythe face 58 of the ring 53 in contact with the Wheel V41.

The wheel 41 is provided with a handle |59 by means of which it may be rotated, thereby rotating the shaft 33, together with the worm 43, and in turn the worm gear .I3 is rotated.

The worm gear I3 has its outer face provided It has been found preferable to indicate these degrees from 0 to 360, reading both to the right -and to the left. The 'body 21 is provided with ya pointer 5I] secured -by the screw SI. This pointer is bent in toward the worm gear I3 so that the movement of the gear I3 and incidentally the spindle II may be read in degrees, on the graduated face of the worm gear I3. l

The main body 21 has an arm 53 extending downwardly and having its lower end formed into a boss 64.

A locking plate is secured to the head stock I 0 by means of cap screws 65. This locking plate is provided with a hole 61 having straight sides 58 and 69.

The boss 54 is drilled out and provided with a shoulder shaft 10 and a spring 1|. The end 12 of the shaft 10 is eccentric to the center line of the main body of the shaft 15. This is clearly shown in Fig. 1. The shoulder 13 of the shaft 10 is engaged by the spring 1| and thereby the shaft 10 is held in its extreme position to the right, as viewed in Fig. 1. A knob 14 is secured to the shaft 10 by means of the taper pin 15 or any other suitable means. This knob is also provided with a handle 16.

'Ihe eccentric portion 12 of the shaft 1|! engages the hole 61 in the plate 65 when the device is in operative relation with the worm gear I3. When a desired setting is obtained, the shaft 15 may be rotated angularly toward the right, as Viewed in Fig. 2, to lock the lathe spindle to the desired position. This locking is ef'- fected as follows: the cam action of the end 12 of the shaft 15 working against the flat surface 58 of the hole 61 clamps the worm 4|) into closer engagement with the worm gear I3, thereby retaining the spindle in this position until such time as the shaft 15 is angularly rotated counterclockwise, thereby establishing normal clear-v left as viewed in Fig. l) and thereby disengages 35 12 from the plate 65, after which the device may be swung back past the vertical line, as shown in the dotted lines in Fig. 1. This places the device completely out of the way and allows the operator Yto use the lathe in anormal manner without having anything in the way.

The device may be readily swung toward the operator and downwardly until the eccentric '12 engages lthe hole B1 Vin the plate 65, whereupon the lathe is instantly ready for dividing.

In the preferred embodiment of the invention as shown, the worm gear I3 has seventy-two teeth and the dial 5I has five major divisions, each advancing the travel of the spindle one degree. The major divisions of the dial are subdivided into ten parts, each corresponding Vto -11-0 of a -deg-ree `of the spindle. 'I'he Vernier 55 further sub-divides the movement into 1/ 100 of a degree, thereby making it possible to divide .a circle into 36,000 parts. The number of teeth on the gear may be greater than or less than seventytwo, but as much of the spacing is done by counting the revolutions of the dial 5|, seventy-two teeth has been found preferable.

A modified form of `a disc or wheel 41 is shown in Figs. 5, 6, and 7. This arrangement isprovided for more accurately setting the disc or wheel 41 relative to the 'Vernier 55 appearing on the member 53. By providing a ldouble Vernier, such as is shown in Fig. '1, itis possible to take care of thousandths of a degreeywhile the Vernier shown in Fig. 1 only takes care of hundredths of a degree.

The Vernier ring '53 has secured thereto an Vinternal ring gear 18. The wheel 41 is tapped and provided with a bushing 19. The bushing 19 forms a bearing for a shaft 8B. This bushing is also provided with arecess carrying a spring ring 8 I. The shaft 80 has one end thereof in the form of a pinion 82 having teeth of the same pitch as the teeth in the internal ring gear 18. The other end of the shaft 80 is provided with a knurled knob 83 by means of which the pinion 82 may be caused to engage the teeth in the ring gear 18. A rounded shoulder 84 is formed on the shaft 80 and adapted to cooperate with the spring ring 8|. The spring, through the medium of the rounded shoulder, holds the shaft 80 with its pinion 82 engaging the ring gear when the knob 83 is positioned inwardly, and holds the shaft with the pinion 82 disengaged when the knob is pulled outwardly.

The knob 83 is usually left in its disengaged or outward position when the device is being operated to contain the rough or coarse adjustments, after which the knob 83 is pushed in with the pinion 82 engaging the ring gear 18, after which the knob 83 may be rotated in either direction and the ne adjustments may be accurately made by means of the double Vernier, thereby making it possible to obtain an accuracy to within 1/1000 of a degree.

While a simple embodiment of the invention is herein shown and described, it is obvious that many modifications and changes may be made without departing from the spirit of the invention as defined in the appended claims.

What is claimed is:

1. In a dividing head adapted to be attached to a lathe, a worm gear adapted to be secured to the spindle of the lathe, a pivot shaft adapted to be supported on one side of the head stock of the lathe, a body member piVoted on said last shaft and adapted to be swung from a Vertical to a horizontal position thereon, a worm shaft journaled in said member, a worm secured to said shaft, a hand wheel having a fiat graduated circumferential face carried by said worm shaft and adapted to rotate the lathe spindle in either direction through the medium of the worm and the worm gear when said body member is swung to a horizontal position, a Vernier ring resiliently supported on said member and having graduations on its face in cooperative relation with said rst graduations, and means partly on said member and partly on said headstock for retaining said Worm and said worm gear in operative relation while a dividing operation is being accomplished and for deeply meshing the teeth of said worm and worm gear after a desired setting of the hand wheel is obtained thereby locking the spindle against further movement, said means including a spring plunger which may be disengaged when the lathe is to be used without said attachment whereby said body may be swung upwardly more than ninety degrees.

2. A dividing head as claimed in claim 1 in which the body member is positioned immediately above the lathe spindle when a dividing operation is to be carried out and in which the body member may be swung backward and out of the way making all parts ofthe lathe accessible to an operator when regular lathe operations are to be carried on.

3. A dividing head as claimed in claim 1 in which the Vernier ring is provided with an internal ring gear and in which the hand wheel is provided with a retractable shaft carrying a pinion whereby said pinion may be used to engage said ring gear for effecting fine adjustment of the hand wheel.

4. A device as claimed in claim 1, in which the body member is provided with a plurality of flutes and in which the Vernier ring is also provided with a plurali-ty of flutes held into engagement with said first flutes by resilient means, whereby the ring may be moved against the resilient means to disengage said utes after which it may be rotated to bring a portion thereof into a position where illumination is best.

5. A dividing head as claimed in claim 1 in which the Vernier ring is provided with an internal ring gear and in which the hand wheel is providedV with a retractable shaft carrying av pinion whereby said pinion may be used to Iengage said ring gear for effecting fine adjustment of the hand wheel, said hand wheel having graduations on the rim thereof and said Vernier having a Vernier scale graduated thereon for effecting ordinary adjustments and at least one division of said Vernier scale being further subdivided to facilitate the making of fine adjustments.

6. A dividing head as claimed in claim 1 in which the Vernier ring is provided with a retractable shaft carrying a pinion whereby said pinion may be used to engage said ring gear for affecting fine adjustments of the hand wheel, said hand wheel having graduations on the rim thereof and said Vernier ring having a rst and a second Vernier scale thereon, the graduations of said second scale being in predetermined fractional ratioto the graduations of said rst scale.

7. A dividing head as claimed in claim 1 in which the Vernier ring is rotatably mounted on the body member, the body member being provided with a retractable dowel adapted to engage any one of a series of depressions in said Vernier ring, whereby said ring may be adjusted to a position most clearly Visible to the operator, and in which means is provided to hold said Vernier ring in close engagement with said handwheel.

8. A dividing head according to claim l, in which the Vernier ring may be adjusted to the scale on the hand wheel in any desired position and in which spring means is provided to retain the Vernier ring in close proximity with said hand wheel.

9. In a device of the character described a pivot shaft positioned on one side of the headstock of a lathe, a worm gear mounted on the spindle of the lathe, a locating plate secured to said headstock and positioned thereon opposite said pivot shaft, a body member supported by said pivot shaft and adapted to be swung from a Vertical to a horizontal position, a worm shaft journaled in said member, a worm secured to said shaft, a plunger pin carried by said member and adapted to engage said locating plate for retaining said worm in operative relation with said gear, a Vernier ring rotatively adjustable on said member, and a hand wheel secured to said shaft in contact with said Vernier ring with the circumferential faces of the Vernier ring and the wheel substantially parallel to each other whereby graduations on the face of the wheel may be read relative to the graduations on the face of the Vernier, said plunger pin being provided with a cam which engages said locating plate when the body member is swung to a horizontal position thereby retaining the worm in operative relation with the worm gear during a dividing operation, said cam being adapted to be rotated to tightly mesh and to lock the worm and worm gear together against rotation or back lash after a desired setting has been obtained.

10. In a device of the character described a pivot shaft positioned on one side of the headstock of a lathe, a worm gear mounted on the spindle of the lathe, a locating plate secured to said he'adstook and vposiisionec' thereon opposite said/pivot shaft, a body mem-ber :supported by said .pivotlsha'ft and 'adapted to be swung yfrom a Vertical to ya horizontal position, a Worm yshaft journal'ed .in said member, `a Worm Vsecured to said shaft, .a plu-nger pin carried `bysaid,rriember and adapted to engage vsazid locating plate for retaining said worm in operative relation with said gear., a Vernier ring rotatively adjustable on said member,iand a hand'whe'el secured to said shaft in contact with said Vernier .ring with the circumferential faces of .the Vernier ring and the wheelsubstantially parallel toxeach other whereby graduation's on the face of the wheel may be rea'd relative to :the graduations on the `face of the Vernier, said body member being provided with a dowel pin which may engage any one of a plurality of doWel holes formed in `said adjustable Vernier tring whereby the latter may be set in a .position most visible to lan operator, and means for holding said Vernier ring into close engagement with .said hand Wheel.

LEO HOLTSCHNEIDER. 

